<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta http-equiv="X-UA-Compatible" content="ie=edge" />
    <title>Document</title>
    <style>
      * {
        margin: 0;
        padding: 0;
      }

      div {
        height: 50px;
        width: 50px;
        outline: 1px solid #000;
      }

      #wrap {
        width: 500px;
        background: red;
      }

      #b {
        position: relative;
        top: 50px;
      }

      #c {
        position: absolute;
        left: 50px;
      }
    </style>
  </head>

  <body>
    <img src="http://r.jumeicd.com/test.jpg" alt="" />
    <div id="wrap">
      <div id="a">a</div>
      <div id="b">b</div>
      <div id="c">c</div>
    </div>
  </body>
</html>
